package tech.bmatch.meituan.util;

/**
 * @program: S1P1FinalProject
 * @description: 计算距离
 * @author: Awake
 * @create: 2018-09-28 17:02
 **/
public class DistanceUtil {
    private static double rad(double d) {
        return d * Math.PI / 180.0;
    }

    public static double getDistance(double lon1, double lat1, double lon2, double lat2) {
        double radLat1 = rad(lat1);
        double radLat2 = rad(lat2);
        double a = radLat1 - radLat2;
        double b = rad(lon1) - rad(lon2);
        double s = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(a / 2), 2) +
                Math.cos(radLat1) * Math.cos(radLat2) * Math.pow(Math.sin(b / 2), 2)));
        s = s * 6371000;
        s = Math.round(s * 10000) / 10000;
        return s;
    }
}

